Intelligent roaming system with over the air programming

ABSTRACT

A mobile station is used by one of a plurality of subscribers of a home area wireless service provider. The mobile station includes a memory for storing a home area wireless network identity and a plurality of preferred wireless network identities. The mobile station further including a controller controlling said mobile station to connect to the home area wireless network when in a home area and controlling said mobile station to connect to one of the preferred wireless networks when outside the home area.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. patent applicationSer. No. 10/121,859, filed on Apr. 15, 2002, which is a continuation ofU.S. patent application Ser. No. 09/567,279, filed on May 9, 2000, whichis now U.S. Pat. No. 6,397,064 which is a continuation of U.S. patentapplication Ser. No. 09/035,850, filed on Mar. 6, 1998, which is nowU.S. Pat. No. 6,148,197, the contents of all of which are incorporateherein in their entireties.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to the field of telecommunications.More particularly, the present invention relates to cellular, PersonalCommunications Services (PCS) and other wireless network systems, andmobile stations having intelligent roaming and over-the-air programmingfeatures.

[0004] 2. Related Application Information

[0005] The present disclosure relates to subject matter contained inU.S. patent application Ser. No. 08/828,172 (filed on Mar. 18, 1997),which is expressly incorporated herein by reference in its entirety. 3.Background and Material Information

[0006] The use of wireless or mobile communication devices has increasedgreatly in recent years. Mobile and cellular telephones have enabledmobile station users to roam over large geographic areas whilemaintaining immediate access to telephony services. Mobile stationsinclude portable units, units installed in vehicles and fixed subscriberstations. Mobile stations comprising cellular telephones or wirelesshandsets are operable in cooperation with cellular or PersonalCommunications Services (PCS) communications systems. Cellularcommunication systems (wireless carriers) typically provide service to ageographic market area by dividing the area into many smaller areas orcells. Each cell is serviced by a radio transceiver (i.e., atransmitter-receiver base station or cell site). The cell sites or basestations may be connected to Mobile Telephone Switching Offices (MTSOs)or Mobile Switching Centers (MSCs) through landlines or othercommunication links, and the MTSOs may, in turn, be connected vialandlines to the Public Switched Telephone Network (PSTN).

[0007]FIG. 1 illustrates the basic components of a conventional cellularnetwork. As shown in FIG. 1, a mobile station 38 may place or receivecalls by communicating with a cell site 30 or a cell site 40, dependingupon the geographic location of the mobile station and the cell coveragearea that is provided by each cell site (i.e., cell coverage area 35 ofcell site 30 or cell coverage area 45 of cell site 40). For purposes ofillustration, mobile station 38 is depicted in FIG. 1 as being able tocommunicate with either cell site 30 or cell site 40, even though themobile station is not illustrated as being located within cell coveragearea 35 or cell coverage area 45. Under normal operating conditions, theextent to which mobile station 38 will be able to communicate with cellsite 30 or cell site 40 will depend on the geographic location of themobile station and the size of the cell coverage area of each cell site.Further, although only two cell sites are depicted in FIG. 1, the entirecellular network may include, for example, more than two cell sites. Inaddition, more than one cell site may be connected to each MTSO.

[0008] Mobile station 38 may include a conventional cellular telephoneunit with a transceiver and antenna to communicate by, for example,radio waves with cell sites 30 and 40. Various air-interfacetechnologies may be implemented to facilitate communication between themobile station and the cell sites. In addition, various serviceofferings may be made available to mobile station users. Cell sites 30and 40 may both include a radio transceiver and be connected bylandlines 16 or other communication links to MTSOs 24 and 28. The PSTN12 is also connected to each MTSO 24 and 28 by landline 16 or othercommunication links.

[0009] The MTSOs 24 and 28 may be conventional digital telephoneexchanges that control the switching between the PSTN 12 and the cellsites 30 and 40 to provide wireline-to-mobile, mobile-to-wireline andmobile-to-mobile call connectivity. The MTSOs 24 and 28 may also (I)process mobile station status data received from the cell sitecontrollers; (ii) handle and switch calls between cells; (iii) processdiagnostic information; and (iv) compile billing information. Thetransceiver of each cell site 30 and 40 provides communications, such asvoice and data, with mobile station 38 while it is present in itsgeographic domain. The MTSOs 24 and 28 may track and switch mobilestation 38 from cell site to cell site, as the mobile station passesthrough various coverage areas. When mobile station 38 passes from onecell to another cell, the MTSO of the corresponding cell may perform a“hand-off” that allows the mobile station to be continuously serviced.

[0010] In the current North American cellular system, any given marketarea may be serviced by up to two competing service providers ofcellular air time communication services (wireless carriers). By FederalCommunications Commission (FCC) regulations, the two competing wirelesscarriers are assigned different groups of frequencies through whichservices are provided. A frequency set typically includes controlchannels and voice channels. The control channels are used forpreliminary communications between a mobile station and a cell site forsetting up a call, after which a voice channel is assigned for themobile station's use on that call. The assigned frequency sets aregenerally referred to as “A band frequencies” and “B band frequencies”.Typically, the A band frequencies are reserved for non-wireline serviceproviders, while the B band frequencies are reserved for the incumbentwireline service providers. While each frequency set for a givencellular service market area is assigned to only one service provider,in different market areas the same frequency set may be assigned todifferent service providers or companies.

[0011] Depending upon which wireless carrier the user of the mobilestation subscribes to, the home frequency set of the user may correspondto the A frequency band or the B frequency band. Whenever a call isplaced by the mobile station, the unit will ordinarily attempt to usethe home frequency set to establish the call. If a call is handledoutside of the user's home market area, then the unit is said to be“roaming” and service will be attempted through a frequency set of anon-home service provider. Typically, the user's home service providerwill have a roaming agreement or reciprocal billing arrangement with thenon-home service provider to permit service to be extended to the user'smobile unit when it is roaming in the non-home service provider's marketarea.

[0012] Whereas cellular typically operates in the 800-900 MHZ range, PCSis expected to operate in the 1.5 to 1.8 GHz range. In North America,the FCC has awarded PCS licenses in six additional bands (i.e., the A-Fcarrier blocks or bands). PCS covers a broad range of individualizedtelecommunication services that let users communicate irrespective ofwhere they are located. With PCS, personalized numbers are assigned toindividuals rather than to the mobile stations, and call completion isperformed regardless of the location of the user. PCS may be implementedthrough conventional macro-cellular techniques or through PersonalCommunications Networks (PCN) that utilize light, inexpensive handheldhandsets and communicate via low-power antennas that are intended tooperate in a similar fashion to that of large scale cellular telephonenetworks, but operate within small geographic or microcellular areas. Itis anticipated that PCNs will operate within the same frequency band inmost countries (e.g., 1850-1990 MHZ), while cellular systems willoperate in different frequency bands in various countries.

[0013] The mobile station may include a memory device, such as a numberassignment module (NAM), in which an assigned phone number and a systemidentification code (SID) and/or System Operator Code (SOC) is stored touniquely identify the home service provider for the unit. In the NorthAmerican cellular system, each provider within a market area is assigneda distinct, fifteen bit SID. IS-136 service providers are also assigneda 12-bit SOC for use throughout all their market areas. In Europe, onthe other hand, the Global System for Mobile Communications (GSM)standard (see, for example, Recommendation GSM 02.11, ServiceAccessibility, European Telecommunications Standards Institute, 1992)defines a process for network selection based on the mobile stationreading the GSM equivalent of the SID, called the Public Land MobileNetwork (PLMN) identity.

[0014] The SID or equivalent system identification number is broadcastby each wireless carrier and is used by the mobile station to determinewhether or not the mobile station is operating in its home network or ifit is operating in a roaming condition. The mobile station makes thisdetermination by reading the SID broadcast in the cellular market areawhere it is located, and comparing it to the home SID stored in the NAMof the cellular phone unit. If the SIDs do not match, then the mobilestation is roaming, and the mobile station must attempt to gain servicethrough a non-home service provider. Due to the imposition of a fixedsurcharge or higher per unit rate, the airtime charges when the mobilestation is roaming are customarily higher than when it is operatingwithin its home network.

[0015] Operation under a roaming condition is often under the control ofthe mobile station user. The user can select whether the mobile stationwill operate in a Home System Only, A Band Only, B Band Only, A BandPreferred, or B Band Preferred operating mode. The user typicallycontrols the system preference and mode operation through menu choice orselection. This current method of roaming control is conventionallyknown as “Preferred System Selection”. In the most common roamingsituation, the mobile station remains on the same band as the homecellular network. That is, if the mobile station is homed to a cellularnetwork with an odd numbered SID (which is normally assigned to an Aband cellular service provider), then the mobile station will obtainservice from the A band cellular service provider when roaming.

[0016] Occasionally, the home service provider will program a mobilestation with negative SIDs. Negative SIDs correspond to SIDs on whichthe mobile station should not obtain service. Negative SIDs may be used,for example, if roaming agreements are not in place between differentcellular service providers. An example of a mobile station that utilizesnegative SIDs is disclosed in BLAIR, U.S. Pat. No. 4,916,728. As analternative to negative SIDs, some mobile stations are programmed withpositive or preferred SIDs. Positive or preferred SIDs are SIDs on whichthe mobile station should attempt to obtain service when selecting acellular carrier frequency. An example of a mobile station that utilizespreferred SIDs is disclosed in BARBER et al., U.S. Pat. No. 5,442,806.The use of preferred SIDs facilitate the selection of a preferredservice provider when the mobile station is roaming.

[0017] With the maturation of mobile communication, a variety ofadvanced services or service offerings have become available to mobilestation users. For example, mobile station users may now elect tosubscribe to messaging services (such as voice mail, text messaging orShort Message Service (SMS)), or other services such as call waitingindication, voice privacy, etc. SMS and other forms of teleservices maybe provided to a mobile station via a message center connected to thecellular network. However, when roaming in another market area, certainwireless carriers in that market may not support all of the advancedservices to which the user subscribes. Consequently, when roaming, theuser may lose use of some or all of the advanced services that the useris accustomed to using.

[0018] Moreover, some large companies have come to depend upon the useof mobile stations and wireless communications. As a result of the largevolume of such usage, they have set up corporate accounts with wirelesscarriers. These accounts are referred to by the wireless carriers asNational Accounts. Preferred roaming rates may be negotiated for aNational Account with particular wireless carriers in certain geographicmarket areas. Thus, when a mobile station roams to one of these marketareas, the National Account subscriber may prefer a different wirelesscarrier from the carrier preferred by the mass market. Furthermore, acorporation may require its personnel to subscribe to particularadvanced services, e.g., a messaging service so the personnel is alwaysreachable. Conventional mobile station equipment and systems do notpermit a corporation to control which carrier roaming personnel will usein order to obtain beneficial rates and to receive selected requiredadvanced services.

[0019] Thus, there is a need in the cellular and mobile networkindustries to provide some form of intelligent or automatic roaming inwhich the mobile station obtains service on the cellular network withwhich the home cellular service provider has the best roaming agreement(or the cellular service provider's own network in the roaming area, ifit is not in the same band as the home system), and/or which supportsthe services the user requires. Two factors have primarily led to thisneed. First, large cellular service providers rarely operate in the sameband in all markets. Second, cellular service providers have chosen tooffer different advanced technologies or services. Consequently, themobile station may have to change bands to obtain the required services.

[0020] Further, there is a need to provide intelligent roamingcapabilities for a mobile station which will not require any changes topresent network interface standards (e.g. IS-41) or air interfacestandards (e.g., IS-136, IS-91A, IS-95). Such features are desirable inorder to permit new intelligent roaming capabilities to be readilyutilized by a mobile station and to allow seamless integration of suchcapabilities without modification to present industry standards. Formore information on network interface standards such as Interim Standard41 (IS-41), see, for example, TIA/EIA-IS-41.5-C, CellularRadiotelecommunications Intersystem Operations: Signaling Protocols,Telecommunications Industry Association, February 1996. For moreinformation on air-interface standards such as Interim Standards 95 and136 (IS-95 and IS-136), see, for example, TIA/EIA-IS-95-A, MobileStation-Base Station Compatibility Standard for Dual-Mode WidebandSpread Spectrum Cellular Systems, Telecommunications IndustryAssociation, May 1995; TIA/EIA-IS-136.1-A, TDMA Cellular/PCS-RadioInterface-Mobile Station-Base Station Compatibility-Digital ControlChannel, Telecommunications Industry Association, October 1996;TIA/EIA-IS-136.2-A, TDMA Cellular/PCS-Radio Interface-MobileStation-Base Station Compatibility-Traffic Channels and FSK ControlChannel, Telecommunications Industry Association, October 1996; andTIA/EIA/IS-136.1-A-1, Addendum No. 1 to TIA/EIA/IS-136.1-A,Telecommunications Industry Association, November 1996.

[0021] Another desirable feature is to provide over-the-air programmingof a mobile station to permit reprogramming of the mobile station withnew intelligent roaming information as it becomes available. Such afeature would permit the “intelligence” that is incorporated into themobile station to be updated and stored with ease, without requiring theuser to bring the mobile station to a technician or operator forreprogramming.

SUMMARY OF THE INVENTION

[0022] According to an aspect of the present invention, an apparatus isprovided for providing preferred wireless carrier information for use bya mobile station when the mobile station is roaming outside of a homemarket area. The invention provides intelligent roaming capabilitiesacross single and multiple hyperbands. The apparatus comprises adatabase, a generator, and a data-providing device. The database storespreferred wireless carrier identities for a plurality of market areasbased upon predetermined classes of service. The generator generates alist of the preferred wireless carrier identities based upon a selectedclass of service and the home market area of the mobile station. Thedata-providing device provides the generated list to the mobile stationdesignated with the selected class of service.

[0023] Preferably, the database further comprises a plurality ofpredetermined home market areas, and the generated list of preferredwireless carrier identities is based upon the selected class of serviceand a selected one of the plurality of home market areas. Moreover, thedata-providing device provides the generated list to the mobile stationdesignated with the selected class of service and the selected homemarket area.

[0024] In another embodiment the database further comprises a pluralityof national accounts, and the generated list of preferred wirelesscarrier identities is based upon the selected class of service and aselected national account. In this embodiment, the data-providing deviceprovides the generated list to each mobile station designated with theselected class of service and the selected national account.

[0025] According to another embodiment the list includes a backupcarrier identity for use in the event service from the preferredwireless carrier is not available. Moreover, the data-providing deviceprovides the list of preferred wireless carrier identities to the mobilestations via wireless communication.

[0026] According to another aspect of the present invention, thegenerator generates the list of preferred wireless carrier identitiesbased upon the plurality of wireless carriers' roaming airtime rates,services or air interface technology provided for each of the pluralityof market areas. The generator may then update the list of preferredwireless carrier identities when one of the plurality of wirelesscarriers changes a communication characteristic (such as roaming airtimerates the wireless carrier charges for a market areas, and services thewireless carrier offers to market areas) for one of the plurality ofmarket areas. The data-providing device provides the updated list ofpreferred wireless carrier identities to all mobile stations previouslyprovided with the list the generator updated.

[0027] Preferably each mobile station is assigned to one of thepredetermined classes of service based upon services to which the mobilestation user subscribes. The list of preferred wireless carrieridentities comprises a plurality of entries indicating a systemidentification number (and/or System Operator Code) and a correspondingfrequency band for each preferred wireless carrier.

[0028] According to another embodiment of the present invention, amobile station is provided that comprises a memory and a selector. Thememory stores a list of preferred wireless carrier identities based upona selected class of service for a plurality of market areas. Theselector automatically selects a preferred wireless carrier from thelist stored in the memory when the mobile station is roaming and entersone of the market areas of the plurality of market areas. Preferably,the mobile station switches to the preferred wireless carrier, selectedfrom the list of preferred wireless carrier identities, to use forcommunication in response to the mobile station roaming to thepredetermined market area. The list of preferred wireless carrieridentities may be downloaded to the memory from a message center via acommunications link established between the message center and thememory. The communications link may comprise a wireless communicationslink and/or a hard-wire or wired communications link. Programming of themobile station unit and entry of preferred wireless carrier identitiesmay also be performed manually by using the keypad of the mobile stationunit.

[0029] According to another embodiment of the present invention, asystem is provided for selecting preferred wireless carriers from aplurality of wireless carriers for use by a mobile station when themobile station is roaming outside of a home market area. The systemcomprises a database, a generator, a data-providing device, a memory anda selector. The database stores preferred wireless carrier identitiesfor a plurality of market areas based upon predetermined classes ofservice. The generator generates a list of the preferred wirelesscarrier identities based upon a selected class of service and the homemarket area of the mobile station. The data-providing device providesthe generated list to each mobile station designated with the selectedclass of service. The memory, provided within the mobile station, storesthe generated list of preferred wireless carrier identities. Theselector selects a preferred wireless carrier from the list stored inthe memory when the mobile station enters one of the market areas of theplurality of market areas. Thus, the mobile station switches to thepreferred wireless carrier, selected from the list of preferred wirelesscarrier identities, for communication in response to the mobile stationroaming to the predetermined market area.

[0030] Preferably, the database further comprises a plurality ofpredetermined home market areas and national accounts. Thus, thegenerated list of preferred wireless carrier identities is based uponthe selected class of service, a selected national account, and aselected one of the plurality of home market areas.

[0031] According to another embodiment of the present invention, amethod is provided for selecting a preferred wireless carrier for amobile station to enable wireless communication when the mobile stationis roaming outside of a home market area. A database of preferredwireless carrier identities for a plurality of market areas based uponpredetermined classes of service is compiled at a predetermined locationremote from the mobile station, and a list of preferred wireless carrieridentities is generated based upon a selected class of service and theplurality of market areas. The list is provided to a storage deviceassociated with the mobile station designated with the selected class ofservice to enable a selection of the preferred wireless carrier. Themethod comprises receiving a signal transmitted by a wireless carriercontaining the wireless carrier's identity, comparing the wirelesscarrier's identity to the database of preferred wireless carrieridentities stored in the mobile station, and switching a communicationsmode within the mobile station so as to obtain service from the highestpriority wireless carrier available.

[0032] According to another embodiment of the present invention, anapparatus is provided for selecting preferred wireless carriers from aplurality of wireless carriers for use by a mobile station when themobile station is roaming outside of a home market area. The apparatuscomprises a database, a generator, a data-providing device, a mobilestation, a memory, and a selector. The database stores preferredwireless carrier identities for a plurality of market areas based uponpredetermined classes of service, predetermined national accounts andpredetermined home market areas. The generator generates a list of thepreferred wireless carrier identities based upon a selected class ofservice, a selected national account, a selected home market area andthe plurality of market areas. The data-providing device provides thegenerated list to mobile stations designated with the selected class ofservice, selected national account and selected home market area. Themobile station is useable in a roaming environment. The memory isassociated with the mobile station and stores the generated list ofpreferred wireless carrier identities. The selector selects a preferredwireless carrier from the list stored in the memory when the mobilestation enters a market area of the plurality of market areas.Preferably, the data-providing device transmits the list of preferredwireless carrier identities via over-the-air programming.

[0033] According to another embodiment of the present invention, amethod is provided for downloading a list of wireless carrier identitiesstored in a database to a mobile station's memory. The database containsthe list of wireless carrier identities from which the mobile stationselects a preferred wireless carrier when the mobile station is roamingoutside of a home market area to use for wireless communication. Thedatabase has a plurality of national account fields, a plurality of homemarket area fields, and a plurality of class of service fields. Eachmobile station is assigned to a national account, a home market area anda class of service. The database determines the list of preferredwireless carrier identities for each class of service field, within eachnational account field within each market area field. Memory is providedwithin the mobile station for storing the list of wireless carrieridentities and preferred wireless carrier identities corresponding tothe mobile station's wireless carrier identities and national account,class of service and home market area. The method comprises determiningwhen the list of wireless carrier identities stored in the mobilestation's memory is outdated. When the list is outdated: determining ifthe mobile station is registered with its home location register;locating the mobile station and downloading an updated list of carrieridentities to the mobile station when it is determined the mobilestation is registered with the home location register; notifying amessage center when the mobile station registers and then downloading anew list of preferred carrier identities to the mobile station when itis determined the mobile station is not registered with the homelocation register (e.g., when delivery is pending). Preferably, thedownloading further comprises a throttling scheme which controls thenumber of mobile stations to which the downloading occurs during apredetermined period of time.

DESCRIPTION OF THE DRAWINGS

[0034] The present invention is further described in the detaileddescription which follows, by reference to the noted plurality ofdrawings by way of non-limiting examples of preferred embodiments of thepresent invention, in which like reference numerals represent similarparts throughout the several views of the drawings, and wherein:

[0035]FIG. 1 illustrates the basic components of a conventional cellularnetwork system;

[0036]FIG. 2A illustrates exemplary components of a cellular or PCSnetwork system implemented according to aspects of the presentinvention;

[0037]FIG. 2B illustrates, in accordance with an aspect of the presentinvention, an exemplary mobile station implemented as a wireless phoneunit;

[0038]FIG. 2C is a general block diagram of the components of the mobilestation of FIG. 2B, in accordance with an aspect of the presentinvention;

[0039]FIG. 3 is a flow diagram of the processes and operations of anintelligent roaming process, according to an embodiment of theinvention;

[0040]FIG. 4 is a diagram of an exemplary architecture that may be usedto download the PSL/IRDB to a mobile station, according to an embodimentof the present invention;

[0041]FIG. 5 illustrates an exemplary message flow for performingover-the-air programming of a mobile station, according to an embodimentof the present invention;

[0042]FIG. 6 illustrates, in accordance with another embodiment of thepresent invention, an exemplary message flow for performing over-the-airprogramming of a mobile station; and

[0043]FIG. 7 is a general block diagram of an exemplary networkarchitecture for implementing and administering the intelligent roamingcapabilities of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] Referring to the accompanying drawings, a detailed description ofthe preferred embodiments and features of the present invention will beprovided.

[0045] The present invention relates to a mobile station withintelligent roaming and/or over-the-air programming features. Thepresent invention permits a mobile station to immediately obtain serviceon a preferred cellular, PCS or other wireless network system meeting asubscriber's service requirements. The selection or designation of sucha system carrier may be configured to comply with, for example,preferences of a corporation having a National Account with the homewireless carrier, when there are multiple bands available.

[0046] According to an aspect of the present invention, a PreferredSystem Identification List (PSL) (for cellular systems) and/or anIntelligent Roaming Database Downloading (IRDB) (for cellular, PCS andother wireless systems) is stored within a memory or storage device ofthe mobile station. When the mobile station is roaming, the PSL or IRDBis accessed to indicate the band where the mobile station will find apreferred system. If the mobile station is capable of operating ineither a cellular or PCS system, the mobile station may access the PSLor IRDB depending on the type of system that it is located in or itscurrent operating mode. The present invention, however, is not limitedto cellular or PCS networks, and may be used with other wirelessnetworks and environments, such as Wireless Communication Services(WCS), Enhanced Specialized Mobile Radio (ESMR), iDENS, and reproposedchannels 60-69. The invention, therefore, may provide intelligentroaming capabilities across single and multiple hyperbands and is notlimited to cellular and PCS systems. Further, the preferred system willbe a system which supports the service requirements of a particularsubscriber. The preferred system may also satisfy the preferences of aparticular National Account reflecting preferred rates negotiated forthat National Account in the market area that the mobile station isroaming in. Further, it is possible that the preferred system be definedand/or selected according to a required or preferred air-interfacetechnology (e.g., TDMA, CDMA, PACS, GSM and PCS-1900) to be utilized bythe mobile station.

[0047] In addition, according to another aspect of the presentinvention, programming of the PSL/IRDB in the mobile station may beperformed over-the-air (i.e., by wireless communication) to permit easyreprogramming of the mobile station with new preferred systeminformation as it becomes available.

[0048] FIGS. 2A-2C illustrate an exemplary network architecture andexemplary system components for implementing the intelligent roamingcapabilities of the present invention. In FIGS. 2A-2C, a mobilestation-based approach is provided for implementing the intelligentroaming capabilities of the invention. According to the mobilestation-based approach of the invention, each mobile station isprogrammed with intelligent roaming capabilities so that it candetermine which system it should obtain service on prior toregistration. As will be appreciated from the following description, themobile station-based approach for providing intelligent roamingcapabilities has several advantages, including the ability to integrateinto conventional cellular or PCS network environments without requiringmodification to the main network components, and without requiring anychanges to current network interface standards (e.g., IS-41) or airinterface standards (e.g., IS-1 36, IS-91A, IS-95).

[0049] In FIG. 2A, exemplary components of a cellular networkimplemented with the features of the present invention are illustrated.Although the present invention is described with reference to a cellularnetwork environment, the present invention may also be applied to othernetwork environments (e.g., PCS or PCN network environments), in which adifferent radio frequency, lower powered cell sites and smaller cellareas are utilized. In FIG. 2A, a mobile station 68 is provided with amemory device 67 for storing a Preferred System Identification List(PSL) and/or Intelligent Roaming Database (IRDB). According to an aspectof the present invention, the PSL/IRDB may be preprogrammed into themobile station prior to activation of the unit and/or may bereprogrammed and updated by using, for example, a physical interface(such as a computer interface) or over-the-air programming techniques,such as those discussed below. The PSL/IRDB indicates the band or bandswhere a mobile station may find a preferred system when roaming. Thatis, the PSL/IRDB may include the SID and/or SOC corresponding to thewireless carrier the mobile station should use for wirelesscommunication in order to obtain the services required by thesubscriber. Furthermore, the PSL/IRDB may include information on theband the mobile station should communicate over in accordance with theNational Account to which the subscriber is a member.

[0050] The mobile station 68 may comprise portable phone units, unitsinstalled in vehicles and fixed subscriber units. By way of non-limitingexample, the mobile station 68 may be implemented as a cellulartelephone unit with a transceiver and antenna (see, for example, FIGS.2B and 2C) to communicate by, for example, radio waves with one or morecell sites. In FIG. 2A, cell sites 75 and 95 are illustrated. The mobilestation 68 may place or receive calls by communicating with cell site 75or cell site 95, depending upon the location of the mobile station andthe cell coverage area that is provided by each cell site. That is, whenmobile station 68 is located within cell coverage area 70 it maycommunicate with cell site 75, and when it is located within cellcoverage area 90 it may communicate with cell site 95. As will beappreciated by those skilled in the art, the actual cell coverage areafor a cell site will depend upon various factors, including the power ofthe transceiver of the cell site, the placement and location of the cellsite, and the topography of the surrounding areas where the cell site islocated. Further, although only two cell sites are depicted in FIG. 2A,the cellular network may of course include more than two cell sites.Moreover, it should be noted that the various components of the cellularnetwork depicted in FIG. 2A are provided for the purpose of illustrationonly, and that other types of network arrangements may of course beprovided to implement the features of the invention. In addition, morethan one cell site may be served by each MTSO.

[0051] Various air-interface technologies (e.g., TDMA, CDMA, PACS, GSMand PCS-1900) may be utilized to facilitate communication between themobile station and the cell sites. Each of the cell sites 75 and 95 mayinclude, for example, a radio transceiver (not shown) and may beconnected by landlines 32 or other communication links to MobileSwitching Centers (MSCs) or Mobile Telephone Switching Offices (MTSOs)54 and 58. Landlines 32 may also be utilized to connect the MTSOs 54 and58 to the Public Switched Telephone Network (PSTN) 82. The MTSOs 54 and58 may also be connected to a Short Message Service Center (SMSC) (notshown in the drawings) to facilitate the delivery of short messages tomobile station 68.

[0052] The MTSOs 54 and 58 may be conventional digital telephoneexchanges that control the switching between the PSTN 82 and the cellsites 75 and 95 to provide wireline-to-mobile, mobile-to-wireline andmobile-to-mobile call connectivity. The MTSOs may provide variousfunctions, including (i) processing mobile station status data receivedfrom the cell site controllers, (ii) handling and switching calls, (iii)processing diagnostic information, and (iv) compiling billinginformation. The transceiver (not shown) of each cell site 75 and 95 mayprovide communication services, such as voice and data communication,with mobile station 68 while it is present in its cell coverage area.Tracking and switching of the mobile station from cell site to cell sitemay be handled by the MTSOs, as the mobile station passes throughvarious cell coverage areas. When, for example, mobile station 68 passesfrom one cell to another cell, the MTSO of the corresponding cell mayperform a “hand-off” that allows the mobile station to be continuouslyserviced if on a voice or data call.

[0053] As shown in FIG. 2B, the mobile station 68 may be implemented asa cellular or wireless phone unit that comprises an antenna 62, aspeaker 64, a microphone 69, a display 65, and a keypad 66 for enteringalphanumeric information. The phone unit of mobile station 68 may beconstructed in a similar fashion to that of a conventional cellulartelephone, with the exception of unique programming and memoryconfigurations and contents for implementing the intelligent roamingaspects of the present invention. Further, the memory 67 of the mobilestation 68 may be configured to handle a greater capacity than that of aconventional cellular telephone, in order to accommodate the PSL/IRDBand other operational information of the present invention.

[0054] Accordingly, mobile station 68 may include a speaker 64 thatcomprises a conventional speaker for converting electrical audio signalsreceived by antenna 62 into acoustic audio signals, and a microphone 69that comprises a conventional microphone for converting voice utterancesof a user from acoustic audio signals into electrical audio signals fortransmission by antenna 62. In addition, display 65 and keypad 66 may beimplemented by conventional display and keypad devices for displayingand permitting entry of alphanumeric and other information. By way of anon-limiting example, display 65 may comprise dedicated status lightsand/or a liquid crystal display (LCD) to indicate the status of thecellular telephone unit (e.g., “No Service”, “Roam”, etc.). Further,keypad 66 may comprise menu selection buttons and/or a conventionaltwelve button, alphanumeric keypad for initiating and receiving calls,and programming or selecting operating conditions for the mobilestation.

[0055] Memory 67 of the mobile station 68 may store the PSL/IRDB andother operational information of the present invention. Memory 67 maycomprise a read-write memory device that has an independent power supplyso the contents will not be effected by power downs of ordinaryduration. By way of non-limiting examples, memory 67 may be implementedby a programmable Electronically Erasable Programmable Read Only Memory(EEPROM), a Complimentary Metal Oxide Semiconductor (CMOS) memory chip,or a conventional Random Access Memory (RAM) with an independent powersupply.

[0056] The handset storage capability provided by memory 67 may varyamong different types or models of the mobile stations. Preferably, lowtier mobile stations should be able to store a minimum of 30 preferredSIDs and high tier mobile stations should be capable of storing aminimum of 100 preferred SIDs. Further, dual band handsets designed tosupport commercially available service carriers, typically can store upto 88 SIDs and/or SOCs. To address the variability in PSL/IRDB storagecapability in mobile stations, the entries in the PSL/IRDB should beprioritized, and the mobile stations can truncate the PSL/IRDB once themaximum storage capacity is reached.

[0057] An exemplary block diagram representation of the components ofthe mobile station 68 depicted in FIG. 2B is provided in FIG. 2C. Asdiscussed above, the cellular telephone unit of the mobile station 68may comprise an antenna 62, a speaker 64, a display 65, a keypad 66, anda microphone 69. The antenna 62 may be connected to a transceiver 63,which in turn is connected to a control system 61. Control system 61 maybe implemented as a microprocessor-based, control system and may beprogrammed to carry out the intelligent roaming features and logic ofthe present invention. The programming of control system 61 may becarried out by any suitable combination or use of software, hardwareand/or firmware. Control system 61 may control the various components ofthe mobile station 68 to permit a user to send and receive calls andprogram the mobile station. In addition, control system 61 may haveaccess to memory 67, in which the PSL/IRDB and other programminginformation is stored, for directing operation of the mobile station. Amore detailed description of the various processes and functions of theintelligent roaming features of the present invention, as well as thelogic steps associated with the intelligent roaming method, is providedbelow with reference to the accompanying drawings.

[0058] Referring now to FIG. 3, an exemplary logic flow diagram of theintelligent roaming process or method of the present invention will bediscussed, in accordance with an embodiment of the present invention.The various processes and operations illustrated in FIG. 3 may becarried out by control system 61 of the mobile station 68 through theuse of programmed logic or firmware. The intelligent roaming process ofthe present invention permits each mobile station to automaticallyobtain service from the most appropriate and/or preferred wirelesscarrier. Although the description below is made with reference to acellular network environment, the various processes and operation mayalso be applied to PCS or PCN network systems.

[0059] In FIG. 3, a mobile station enters an initialization state atstep S.2, when the mobile station is powered ON, changes systems, is ina “No Service” condition, or when an Intelligent Roaming mode (IR Mode)has been selected by the user. After the mobile station has beeninitialized, the mobile station first scans for its home band (i.e., theset of frequencies corresponding to its home network system) at step S.4to locate a control channel. The set of frequencies corresponding to thehome band of the mobile station may be programmed into the mobilestation's memory (e.g., memory 67) by the home system service provider.

[0060] At step S.6, the mobile station determines whether it is in itshome system or market area. Whether or not the mobile station is locatedin its home market area may be determined by analyzing the SID, SOC orequivalent system identification number of the cellular service providerfor the area in which the mobile station is located. By comparing theSID or SOC received on the control channel with the home SID or SOC ofthe home service provider, the mobile station may determine whether itis located in its home system. As described above, the home SID or SOCmay be stored in the NAM of the mobile station, or may be stored inanother appropriate memory or storage device of the mobile station. Forexample, the home SID or SOC may be stored separately from the PSL/IRDBof the mobile station, or may be stored in memory 67 as part of thePSL/IRDB.

[0061] If the mobile station determines that it is located in its homemarket area, then at step S.8, the mobile station will stay on that bandand obtain service from the home wireless carrier/cellular serviceprovider. However, if the mobile station determines that it is not inits home market area, then at step S.10 the PSL/IRDB stored in themobile station will be accessed and searched at step S.12 to determineif the received SID or SOC corresponds to the preferred wireless carrierfor the current market area. If the received SID or SOC corresponds tothe SID or SOC of the preferred wireless carrier, at S.14 the mobilestation 68 obtains service from the current wireless carriertransmitting the received SID or SOC. However, if at S.12 the mobilestation 68 determines the current SID or SOC is not the preferred SID orSOC, the mobile station obtains service from the band indicated in thePSL/IRDB at step S.16.

[0062] In accordance with an aspect of the present invention, thePSL/IRDB stored in the mobile station may comprise a table of entriesincluding the SIDs and/or SOCs and corresponding frequency band(s) ofthe preferred service providers for each market area. The preferredservice providers may correspond to cellular service providers themobile station's home system has a reciprocal agreement or billingarrangement with to provide service when the mobile station is roaming.In addition, the preferred system may also be defined and/or selectedaccording to a preferred or required air interface technology. Entriesin the PSL/IRDB may be the SIDs or SOCs associated with each regionwithin which one or more preferred service providers exist (e.g., thePSL/IRDB may include entries for one or more of the SIDs and/or SOCsassigned in the North American cellular system). If more than onepreferred or target system exists for a given region, then the preferredsystems in an PSL/IRDB entry may be listed in order of preference and/orthe air interface technology may be provided for each preferred systemso that the mobile station may select the most appropriate system forthat region. An example of the information fields or elements for thePSL/IRDB and PSL/IRDB entries is provided below in Table 1. In thePSL/IRDB, there is one carrier per market area. However, in the casewhere the carrier covers only part of the market area, a second carriermay also be provided. For example, PCS Service Provider A covers onlypart of the Washington, D.C. market area. If the preferred carrier inWashington, D.C. is PCS Service Provider A and the mobile station 68 isoutside of the PSC Service Provider A's coverage, the mobile stationmust communicate via a different carrier and, therefore, the secondcarrier for that market area (Washington, D.C.) from the PSL/IRDB isused. TABLE 1 PSL/IRDB Entries Market Area SID and/or SOC FrequencyMarket Area 1 Preferred SID/SOC for Market Area Corresponding 1 (andAlternative SID/SOC if required) Band Market Area 2 Preferred SID/SOCfor Market Area Corresponding 2 (and Alternative SID/SOC if required)Band . . . . . . . . . Market Area N Preferred SID/SOC for Market AreaCorresponding N (and Alternative Band SID/SOC if required)

[0063] In Table 1, N represents the total number of market areas withinthe country/geographic area the cellular/PCS system covers.

[0064] Because some markets operate using multiple SIDs, PSLs/IRDBs willneed to be administered on a per SID basis. Even within a given market(SID), different PSLs/IRDBs will be required to support differentclasses of service. This can be demonstrated by an example of twocellular subscribers who roam into a geographic area (e.g., Austin) fromthe same market (e.g., Dallas). If one subscriber desires to receiveShort Message Service, they may roam to a service provider supportingthat service (e.g., Service Provider A) while the other subscriber whorequires only voice (a class of service hereinafter referred to aswireless POTS (Plain Old Telephone Service)) may roam to another serviceprovider providing a more attractive roaming rate (e.g., ServiceProvider B). This is required because not all service providers willsupport all classes of service. The roaming paradigm must change toaccommodate scenarios like these.

[0065] Table 2 lists exemplary wireless features of the mobile stationsand identifies them with classes of service, based on the requirementsto provide these features. TABLE 2 Classes of Service For WirelessFeatures Requirements to Resulting Class Wireless Feature ProvideFeature of Service Wireless Plain Old Roaming Agreement (RA) Class ofService 1 Telephone Service (POTS) Analog Circuit- RA Class of Service 1Switched Data Private Systems RA, Digital Control Channel Class ofService 2 (PSIDs) (DCCH) Short Message Service RA, DCCH Class of Service2 (SMS) Message Waiting RA, DCCH Class of Service 2 Indicator (MWI)Extended Battery Life RA, DCCH Class of Service 2 TDMA Packet Data RA,DCCH+, DTC+ (where + Class of Service 3 indicates that the channelrequires enhanced capabilities to support this service) Voice PrivacyRA, DCCH, Digital Traffic Class of Service 3 Channel (DTC) DigitalCircuit- RA, DCCH, DTC Class of Service 3 Switched Data

[0066] National Accounts may require different PSLs/IRDBs than the moregeneral mass market. For instance, preferred roaming rates may benegotiated for a National Account in one geographic location which wouldcause the National Account subscriber to prefer a service providerdifferent from the service provider preferred by the mass marketsubscribers.

[0067] An exemplary National Accounts database according to a preferredembodiment of the present invention is illustrated below in Table 3.Without any loss in generality, Table 3 shows PSLS instead of IRDBs.Because a wireless carrier in different home market areas typically hasdifferent roaming partners, each home market's PSL/IRDB may bedifferent. Consequently, the parameters and information fields in Table1 should be replicated for each home market area. Thus, for each homemarket area, a PSL/IRDB is generated depending on the National AccountGroup a subscriber is a member of and the class of service required bythe subscriber. In Table 3, there are n classes of service (COS) and mNational Accounts (NA). NA₀ represents the mass market account. Thedatabase of Table 3 may be stored within a switch or computer in thecentral office (message center). Although one such database should beprovided for each home market area, one database could serve multiplemarkets. In Table 3, a National Account database is illustrated for homemarket area 1. This database may serve or be used for other home marketareas (e.g., home market areas 2 through p, where p is the total numberof home market areas), or separate databases may be provided for eachhome market area that exists. TABLE 3 Database Representation HomeMarket Area 1 COS₁ COS₂ . . . COS_(n) NA₀ PSL₀₁ PSL₀₂ PSL_(0n) NA₁ PSL₁₁PLS₁₂ PSL_(1n) . . . . . . . . . . . . NA_(m) PSL_(m1) PSL_(m2) PSL_(mn)

[0068] The size and configuration of the National Accounts database maybe configured according to system preferences and/or requirements. Table4 below indicates an exemplary configuration for the databases,indicating the number of databases and the size of each field for eachdatabase. TABLE 4 Database Sizing Entry Size Comment Number of Home  32Market Area databases Classes of Service  16 Some reserved for futureuse, e.g., PCS-1900, CDMA National 512 Accounts Preferred SIDs 100 max.per COS/NA per Home Market Area Alpha Tags  3 per Home SID For Home SIDAlpha Tag, Preferred SID Alpha Tag, Neutral SID Alpha Tag

[0069] In Table 4, alpha tags relate alpha numeric system identitiesthat are typically displayed on the mobile station's display screen uponregistration with the system. The alpha tages may be stored in thememory or the PSL/IRDB of the mobile station.

[0070] The PSL/IRDBs are generated for each National Account upon theestablishment of a National Account. A representative of the companycreating the National Account typically selects the preferred carrierfor each market area depending on the airtime rates and the class ofservice required. For example, the wireless carrier with the mostfavorable airtime rates is typically selected for each market area.However, if it is determined to be imperative to maintain a class ofservice, the mobile station will switch to the wireless carriersupporting the required class of service, even if a less favorable rateresults.

[0071] Several events may cause the PSL/IRDB to become outdated. Forexample, the PSL/IRDB may change whenever the mobile station changes itsclass of service. Also if the home market service provider establishes anew roaming agreement with a carrier, the rates may change and newPSLs/IRDBs must be generated. Another time the PSL/IRDB may change iswhen a carrier adds a new technology or class of service. Once thePSLs/IRDBs become outdated, a new list should be downloaded to allmobile stations 68 affected by the update. Such downloading may becarried out by utilizing over-the-air programming (OAP) techniques, suchas those discussed below.

[0072] Typically, when the mobile station is initially activated, themobile station 68 is programmed with the PSL/IRDB by an interface thatphysically connects to the mobile station. The PSL/IRDB for eachparticular mobile station is selected according to the mobile station'shome market area, National Account and class of service. Thesedesignators are assigned to each mobile station upon initial activation.However, the database may be downloaded by an interface that usesover-the-air programming (OAP) and downloading. Further, programming ofthe mobile station 68 may be performed manually through use of thekeypad of the mobile station.

[0073] In order to provide increased flexibility, such programming anddownloading of PSL/IRDB information may be performed over-the-air. Inaccordance with an aspect of the present invention, over-the-airprogramming of the PSL/IRDB allows the PSL/IRDB to be initiallydownloaded and/or updated to the mobile station without requiring theuser to bring the mobile station into a service center. The over-the-airprogramming capability of the present invention provides severaladvantages, including improving the ease by which the mobile station canbe programmed with new preferred system information as it becomesavailable to the home cellular or PCS operator.

[0074]FIG. 4 illustrates a top level architecture or arrangement for thePSL/IRDB downloading using Over-the-Air Activation (OAA) andOver-the-Air Programming (OAP). As shown in FIG. 4, an applicationreferred to as an Over-the-Air Activation Function (OTAF) 100 is storedat an external platform. The OTAF 100 may be implemented with softwareor programmed logic, and be adapted to perform the various functionsdescribed herein. The OTAF 100 may be provided together with a databaseincluding the tables and entries described above with reference toTables 3 and 4. The platform at which the OTAF 100 and database areprovided may be a special purpose platform or may be incorporated intoan existing platform, such as a Short Message Service Center (messagecenter), a local switch, a Home Location Register (HLR), or a ServiceControl Point (SCP) of an Advanced Intelligent Network (AIN). In orderto perform administrative functions on the database of the OTAF 100,including populating and/or modifying PSL/IRDB entries in the database,a database administration access mechanism 101 may be provided. Thedatabase administration access mechanism 101 may be provided locally orremotely from the OTAF 100 and may be controlled and operated by a humanoperator. For example, the database administration mechanism 101 mayinclude an operator terminal provided at the Message Center (MC) or atthe Customer Service Center (CSC). In addition, the databaseadministration access mechanism 101 may include any known type of inputsource. Exemplary access schemes into the OTAF 100 include: (1) an OTAFplatform administrative terminal, (2) a TCP/IP feed directly from theCustomer Service Center (CSC), and (3) a dial-up modem connection from aremote facility. Preferably, the information is input via the ShortMessage Peer-to-Peer (SMPP) protocol which runs over TCP/IP.

[0075] In accordance with an aspect of the invention, the database ofthe OTAF 100 may also maintain a subscriber database of all activemobile stations that are capable of receiving a new roaming database ortable entries. The subscriber database may be generated by the CustomerService Center (CSC) 102 and provided as input to the OTAF 100. When acustomer activates (or reactivates) a mobile station 68, the CSC 102enters a subscriber profile into the subscriber database. The profilepreferably includes routing identification information, such as MobileIdentification Number (MIN), Electronic Serial Number (ESN) and PrivateSystem IDs (PSIDs) for downloading into the mobile station 68. At thistime, the subscriber is preferably assigned a class of service (COS)designator and a home SID which are also entered into the subscriberdatabase. From this subscriber database, the OTAF 100 is able togenerate and send out the new or updated roaming database to each mobilestation on record. For this purpose, the OTAF 100 may include agenerator that generates a list of preferred wireless carrier identitiesfor the mobile station by comparing the entries and information in thedatabase with the profile criteria of the mobile station, including theselected COS, National Account and/or the home market area of the mobilestation. In addition, a preferred air-interface technology may bedefined for the mobile station by the CSC 102 and provided as input tothe OTAF 100 as additional criteria for generating a list of preferredcarrier identities for the mobile station. The appropriate PSL/IRDBentries are then forwarded to the mobile station by the OTAF 100.

[0076] More particularly, according to an aspect of the invention, thePSL/IRDB entries may be generated and downloaded to each mobile stationin accordance with the following procedure.

[0077] When a subscriber calls the Customer Service Center (CSC) 102 toactivate a mobile station handset 68, the CSC 102 representative assignsa MIN for the handset, identifies the features to which the subscriberis allowed, and determines the National Account status (either massmarket (NA₀) or a particular National Account). The CSC 102automatically identifies the Home SID based on the MIN, and the Class ofService based on the subscriber's features. The CSC 102 then sends theMIN, ESN, Home SID, COS, and National Account (NA) to the OTAF 100. TheCSC 102 may also determine and send the preferred air-interfacetechnology to be utilized by the mobile station as additional profilecriteria to the OTAF 100, as noted above. The OTAF 100 matches the Homemarket area or SID, COS, and/or NA with a PSL/IRDB entry in thedatabase, to generate a list of preferred wireless carrier identitiesfor the mobile station. If provided by the CSC 102, other criteria mayalso be utilized to select preferred carriers, such as the air-interfacetechnology defined for the mobile station. After generating the list ofpreferred wireless carrier identities, the OTAF 100 then proceeds toprogram the handset using, for example, the defined IS-136A message set.

[0078] In the reprogramming scenario, the PSL/IRDB will be downloadedwith other OTAF information similar to that for new activations. Inother words, upon reprogramming, if the National Account (NA), COS, MINand/or any other parameters change, each changed parameter isreprogrammed or downloaded into the mobile station 68 along with the newPSL/IRDB. If none of the parameters have changed, only the updatedPSL/IRDB is downloaded to the mobile station 68.

[0079] When a PSL/IRDB needs to be updated, personnel may enter the new(or modified) roaming PSL/IRDB into the OTAF 100 via, for example, anexternal terminal entry or the database administration mechanism 101. Awireless carrier's personnel will then set a flag in the OTAF 100indicating that a new PSL/IRDB for a particular COS/NA has been enteredand needs to be sent to mobile stations designated with that COS/NA.

[0080] The OTAF 100 then queries the subscriber's Home Location Register(HLR) 104 via, for example, one or more Signaling Transfer Points (STP)110 to identify and determine the subscriber's mobile station 68 statusand location. A throttling scheme is active at this point to limit thenumbers of queries sent to each HLR 104 in order to prevent overload.For example, a craft settable throttling mechanism may be utilized inorder to prevent flooding of the Home Location Register (HLR) 104 withSMSREQ messages or any other known message protocol for communicationwith an HLR. The message center (MC) or platform supporting the OTAF 100preferably has an internal teleservices ID prioritization scheme whichpushes messages to the top of the queue based on the teleservices ID.For instance, if multiple messages are being stored for a singlesubscriber, it may be desired to ensure that the mobile station has thelatest roaming database installed before a Cellular MessagingTeleservice (CMT) message is sent. OAA, OAP and CMT are identified bydifferent teleservice IDs.

[0081] If the mobile station 68 is available, the HLR 104 will returnlocation information (with, for example, a SMSNOT message) to the OTAF100 (by way of, for example, one or more STPs 110) to permit routing ofthe PSL/IRDB entry information to the mobile station 68 via the servingMobile Switching Center (MSC) and the wireless network infrastructure.As illustrated in FIG. 4, the wireless network infrastructure forcommunicating with the mobile station 68 may include one or more MobileSwitching Centers (MSC) 106 and Base Stations (BS) 108. Once thelocation of the mobile station 68 is determined from the HLR 104 (and/orVisiting Location Register (VLR)—not illustrated in FIG. 4), the OTAF100 will route (via the appropriate STP 110) the database information topermit the serving MSC 106 and BS 108 to relay the PSL/IRDB entryinformation to the mobile station 68 by wireless communication,including transmission over-the-air. The wireless communication betweenthe BS 108 and the mobile station 68 may preferably use the IS-136standard, although any known standard may be used. Communication betweeneach MSC 106 and BS 108 may use conventional wired or wirelesscommunication links.

[0082] If the mobile station 68 is unavailable, the HLR 104 will set aninternal flag to notify the OTAF 100 when the handset or mobile stationbecomes active and/or registers. When the OTAF 100 receives locationinformation on the mobile station 68, the OTAF 100 sends the new roamingPSL/IRDB to the mobile station 68, as described above. Thereafter,normal OAA and/or OAP logic flow or processing may be carried outaccording to industry or forum defined standards and protocols (such asthe standards and protocols set for IS-136 by the Universal WirelessCommunications Committee (UWCC) or an open industry forum/group).

[0083] As described above, a throttling scheme may be used to preventoverloading of the network. For example, if a new roaming agreement isreached with another wireless carrier, many handsets will be effected.Consequently, the downloading of the new databases to all of the mobilestations will overload the network. Therefore, a craft-settablethrottling mechanism, i.e., to identify the number of maximum databasesto update at a time, is provided. Furthermore, the throttling mechanismmay allow favoring of one National Account over another when updatingthe databases, i.e., downloading the new data to subscribers of oneNational Account before downloading data to subscriber of other NationalAccounts. Conventional throttling techniques may be used for thispurpose.

[0084] Referring now to FIGS. 5 and 6, exemplary embodiments of thepresent invention for providing over-the-air programming of the PSL/IRDBto the mobile station will be described. In accordance with theinvention, over-the-air programming of the PSL/IRDB may be accomplishedas part of the Over-the-Air Activation Teleservice (OATS) defined in theAddendum to Interim Standard 136A (IS-136A) of the North AmericanCellular System, or as a different teleservice. A teleservice isgenerally an end-to-end data application between a mobile station and anetwork entity (e.g., a message center or Over-the-Air ActivationFunction (OTAF)) that is typically independent of and transparent to aBase Station/Mobile Switching Center/Interworking Function (BMI). TheBMI provides the teleservice transport, but is not directly involved inprocessing the actual teleservice data. For additional informationconcerning OATS, OTAF and BMI, see the Addendum to IS-136 Revision Acontained in TIA/EIA/IS-136.1-A-1, Addendum No. 1 to TIA/EIA/IS-136.1-A,Telecommunications Industry Association, November 1996, the disclosureof which is expressly incorporated herein by reference in its entirety.For information on over-the-air activation (OAA) and over-the-airprogramming (OAP), see “BellSouth Cellular and Southwestern Bell JointRequirements Document: Interim Over-The-Air Activation for 850 MHzIS-136 Mobile Stations”, Version 1.1, Feb. 17, 1997, and “IntelligentRoaming”, Contribution Submitted by AT&T Wireless Services, Inc. to TIATR45.3.6, Apr. 28-30, 1997, the disclosures of which are expresslyincorporated herein by reference in their entireties.

[0085] According to one embodiment of the present invention, theover-the-air programming of the PSL/IRDB may be made part of OATS, bystandardizing and providing new information elements to program themobile station with the PSL/IRDB, i.e., the intelligent roaming data(see, for example, FIG. 5 and the accompanying description providedbelow). Alternatively, in accordance with another embodiment of thepresent invention, the over-the-air programming of the PSL/IRDB may bemade part of the OATS by embedding the new information as messageswithin the System Operator Code (SOC) Specific Request message definedfor OATS. The System Operator Code (SOC) is a twelve bit value that isbroadcasted on the control channel (normally a DCCH) and used toidentify which operator is providing service. In the two embodimentsdescribed below, if a PSL/IRDB entry is duplicative of another PSL/IRDBentry stored in the mobile station, then a new PSL/IRDB entry mayoverwrite the old PSL/IRDB entry in memory. In addition, if there is alarge quantity of PSL/IRDB information that needs to be stored in themobile station, the initial downloading of all of the PSL/IRDBinformation may be performed by a physical interface or connection(e.g., during manufacture of the mobile station), and subsequent updatesor reprogramming of specific data in the PSL/IRDB may be performedover-the-air.

[0086]FIG. 5 illustrates, in accordance with an embodiment of thepresent invention, an exemplary diagram of message flows between aMobile Station (MS) and the Base Station/Mobile SwitchingCenter/Interworking Function (BMI) for implementing over-the-airprogramming of the PSL/IRDB based on OATS. The MS comprises a stationused by a cellular or PCS subscriber to access network services over anair interface. The MS may be implemented as a portable phone unit, aunit installed in a vehicle or a fixed subscriber station. Base stationsprovide the ability for each MS to access network services over an airinterface. An MSC or MTSO is connected to at least one base station, andmay use inter-working functions to connect to other networks.

[0087] According to an aspect of the present invention, the BMI includesthe network entity that stores a centralized or master PSL/IRDBdatabase, and that oversees the programming of the PSL/IRDB in each ofthe mobile stations. The same network entity that provides OATS may alsoprovide the over-the-air programming of the PSL/IRDB for the mobilestations. OATS may be used on either a Digital Traffic Channel (DTC) ora Digital Control Channel (DCCH). If there is a large quantity ofPSL/IRDB information to be programmed, multiple Download Requestmessages may be sent to the mobile station in order to program all ofthe intelligent roaming data. In FIG. 5, CSC is an acronym for theCustomer Service Center, and NAM is an acronym for Number AssignmentModule in the mobile station.

[0088] According to the embodiment of FIG. 5, the existing OATS messagesare used for over-the-air programming of the PSL/IRDB in the mobilestation. However, new information elements and fields are defined,according to the present invention, for some of the OATS messages inorder to program the mobile station with the PSL/IRDB information. Theparticular OATS messages that are modified to incorporate the PSL/IRDBinformation include, for example, the Confirmation Data Request, theConfiguration Data Response, the Download Request, and the DownloadResult messages, which are indicated in FIG. 5 and discussed in detailbelow.

[0089] When a Configuration Data Request message is sent from the BMI tothe MS at step S.200, specific configuration data blocks are solicitedfrom the mobile station. An example of the contents of a modifiedConfiguration Data Request message, according to an aspect of theinvention, is indicated below in Table 5. In Table 5, and in thesubsequent tables discussed below, the “Type” may be either Mandatory(M) or Optional (O), and the “Length” is given in bits. Further, forTable 5 and the subsequent tables provided herein, the new informationelements and modifications to the OATS-based messages are underlined inthe tables. TABLE 5 Configuration Data Request Information Element TypeLength Message Type M 6 Remaining Length (in Octets) M 8 ConfigurationData Block Map M 16

[0090] As shown in Table 5, the Configuration Data Request may bemodified to include a new entry in the Configuration Data Block Map. TheConfiguration Data Block Map is an information element or data messagethat provides a list of the Configuration Data Blocks for which the BMIrequests configuration information from the MS. As shown below inexemplary embodiment of Table 6, the Configuration Data Block Map mayinclude specific values for a NAM Configuration Data Block request and aNon-Public System Configuration Data Block request. In addition,according to the present invention, values may be provided for a BandInfo request and System Access List request for the purpose ofprogramming the mobile station. A more detailed discussion of the BandInfo and System Access List data blocks of the present invention isprovided below. In Table 6, and the subsequent tables, the value “X”(where present) represents that the value may be assigned either a valueof zero or value of one. TABLE 6 Configuration Data Block Map ValueFunction XXXX XXXX XXXX NAM Configuration Data Block requested XXX1 XXXXXXXX XXXX Non-Public System Configuration Data Block XX1X requested XXXXXXXX XXXX Band Info requested X1XX XXXX XXXX XXXX System Access Listrequested 1XXX

[0091] At step S.204, a CSC Challenge Request is sent from the MS to theBMI in response to receiving the Configuration Data Request. The CSCChallenge Request that is sent by the MS may be similar to theOATS-based CSC Challenge Request. Following step S.204, an OATS-basedCSC Challenge Response is sent by the BMI at step S.208 in response tothe CSC Challenge Request from the MS, and then a Configuration DataResponse is sent at step S.212. While the OATS-based CSC ChallengeRequest and the CSC Challenge Response are not modified, the standardConfiguration Data Response message for OATS is modified, according tothe present invention, with new information elements so that the mobilestation can provide, for example, information to the BMI on thecurrently stored intelligent roaming information (i.e., Band Info andPSL/IRDB). Table 7A shows an exemplary configuration of the modifiedConfiguration Data Response, and Table 7B illustrates exemplaryparameter type codes for the optional information elements in theConfiguration Data Response of Table 7A, in accordance with an aspect ofthe invention. In Table 7A, and the subsequent tables, the “*”represents that the maximum bit length or range of the bit length isonly limited by the defined length of the overall application layermessage. TABLE 7A Configuration Data Response Information Element TypeLength Message Type M  6 Remaining Length (in Octets) M  8 NAMConfiguration Data Block 0 8 or 212-648 Non-Public Configuration DataBlock 0 12-* System Operator Code (SOC) 0 16 Index Code 0 36 Band Info 027 System Access List 0 35-*

[0092] TABLE 7B Parameter Codes for Optional Information ElementsParameter Type Code NAM Configuration Data Block 0001 Non-PublicConfiguration Data Block 0010 System Operator Code (SOC) 0011 Index Code0100 Band Info 0101 System Access List 0110

[0093] As shown in Table 7A, the Configuration Data Response message ofthe present invention is similar to the Configuration Data Response forOATS except that for the invention a Band Info information element and aSystem Access List information element are also included in the message.The Band Info information element may contain data that identifies, forexample, the home band and the secondary band, as well as other data tosupport intelligent roaming. The System Access List information elementmay contain PSL/IRDB data entries for the mobile station to use inidentifying the preferred system(s) to access in an intelligent roamingmode. Examples of the data fields for the Band Info and System AccessList information elements are provided below with reference to Tables 9and 14, respectively. Exemplary parameter type codes that may be usedfor the optional information elements of the Configuration Data Responseof Table 7A are provided in Table 7B. As shown in Table 7B, newparameter type codes may be provided for the Band Info and the SystemAccess List information elements.

[0094] Referring to FIG. 5, after the Configuration Data Responsemessage has been sent to the BMI, a Download Request message is sent tothe MS at step S.216. The Download Request message is sent to the mobilestation in order to download specific configuration data. According tothe present invention, the Download Request message may be modified toinclude the Band Info and System Access List information elements. Anexample of the modified Download Request Message is shown in Table 8A,and Table 8B includes exemplary parameter type codes that may be usedfor the optional information elements in the Download Request message ofTable 8A. TABLE 8A Download Request Information Element Type LengthMessage Type M 6 Remaining Length (in Octets) M 8 NAM Download 0 *Non-Public Download 0 * Band Info 0 26 System Access List 0 35-*

[0095] TABLE 8B Parameter Codes for Optional Information ElementsParameter Type Code NAM Download 0001 Non-Public Download 0010 Band Info0011 System Access List 0100

[0096] The Band Info information element that is provided as part of theConfiguration Data Response message and Download Request message may beused to identify, for example, the home band, the probability block mapfor the home band, and the secondary band to support the intelligentroaming capabilities of the present invention. The Band Info informationelement is a new OATS information element. Table 9 illustrates anexample of a Band Info information element, according to an aspect ofthe present invention. TABLE 9 Band Info Field Length Parameter Type 4SID Alpha Tag Control 1 Home Band 3 Probability Block Map 16 SecondaryBand 3

[0097] In the Band Info information element, a Parameter Type code(e.g., 0011) may be included to indicate the parameter type, and a SIDAlpha Tag Control field (i.e., a SAT_Ctrl field) may be included toindicate when the Home SID Alpha Tag should be displayed. If, forexample, the SID Alpha Tag Control field is set to one, then the mobilestation will be instructed to display the Home SID Alpha Tag. If, on theother hand, the SID Alpha Tag Control field is set to zero, the Home SIDAlpha Tag will not be displayed. A Home Band field may also be providedin the Band Info information element to indicate the frequency band forthe home system. Further, as shown in Table 9, a Probability Block Mapfield may also be provided to indicate the most likely probabilityblocks in which a control channel may be found by the mobile station.Tables 12 and 13 are, respectively, exemplary Home Band and ProbabilityBlock Map fields that may be utilized to implement the features of thepresent invention.

[0098] As further shown in Table 9, the Band Info information elementmay include a Secondary Band field. The Secondary Band field may beprovided to identify the secondary frequency band for the mobile stationto scan if no acceptable control channels can be found on the home band.The Secondary Band field may be coded in a similar manner to the HomeBand field described below (see, for example, Table 12).

[0099] In response to the Download Request message from the BMI at stepS.216, a Download Result message is sent at step S.220 from the MS tothe BMI. In accordance with the present invention, the Download Resultmessage may be a modified OATS message that includes a Download ResultMap information element. The Download Result Map information elementprovides feedback to the BMI on the results of the data block downloads.Table 10A illustrates an exemplary, modified Download Result message,and Table 10B illustrates exemplary parameter type codes of the optionalinformation elements in the Download Result message of Table 10A. Inaddition, Table 11 is an exemplary Download Result Map informationelement which may be provided as part of the Download Result message ofTable 10A. TABLE 10A Download Result Information Element Type LengthMessage Type M  6 Remaining Length (in Octets) M  8 Download Result MapM 16 Parameter Error 0 *

[0100] TABLE 10B Parameter Codes for Optional Information ElementsParameter Type Code Parameter Error 0001

[0101] TABLE 11 Download Result Map Value Function XXXX XXXX XXXX NAMdownload unsuccessful XXX0 XXXX XXXX XXXX NAM download successful XXX1XXXX XXXX XXXX Non-Public download unsuccessful XX0X XXXX XXXX XXXXNon-Public download successful XX1X XXXX XXXX XXXX Band Info downloadunsuccessful X0XX XXXX XXXX XXXX Band Info download successful X1XX XXXXXXXX XXXX System Access List download unsuccessful 0XXX XXXX XXXX XXXXSystem Access List download successful 1XXX

[0102] After step S.220 in FIG. 5, the subsequent OATS messages may besent in standardized format to complete the over-the-air programming ofthe mobile station. That is, at step S.224, a NAM Commit Result messagemay be sent from the BMI to the MS, and then a CSC Challenge Requestmessage may be sent at step S.228 from the MS to the BMI. Thereafter, atstep S.232, a CSC Challenge Response message may be sent to the MS, andthen a NAM Commit Result may be sent from the MS to the BMI in stepS.236. At this point, the PSL/IRDB and other intelligent roaming data isupdated in the memory of the MS, and the MS may proceed to performintelligent roaming with the updated information.

[0103] As described above, the message flow for over-the-air programmingof the mobile station may be achieved by utilizing new informationelements that are sent based on an OATS message flow. According to anaspect of the present invention, the existing OATS messages that aremodified to include these new information elements include, for example,the Configuration Data Request message, the Configuration Data Responsemessage, the Download Request message and the Download Result message,as described above. The new and modified OATS information elements thatare provided include, for example, the Band Info information element,which is described above with reference to Table 9, the ConfigurationData Block Map information element, which is described above withreference to Table 6, and the Download Result Map information element,which is described above with reference to Table 11. Other newinformation elements and fields may also be provided to implement theintelligent roaming capabilities of the present invention. Examples ofthese information elements and fields are discussed below with referenceto Tables 12-19.

[0104] Table 12 illustrates an exemplary list of coded values for theHome Band field, which may be provided as one of the fields in the BandInfo information element (see, for example, Table 9). As discussedabove, the Home Band field may indicate the frequency band for the homesystem of the mobile station. The Home Band field may be three bits inlength and assigned one of a plurality of coded values to indicate thefrequency band of the home network provider. As shown in Table 12,values may be assigned for both cellular A and B bands, as well as for1900 MHZ PCS bands. TABLE 12 Home Band Value Function 000  800 MHZ ABand 001  800 MHZ B Band 010 1900 MHZ A Band 011 1900 MHZ B Band 1001900 MHZ C Band 101 1900 MHZ D Band 110 1900 MHZ E Band 111 1900 MHZ FBand

[0105] Table 13 illustrates an exemplary coding of values for theProbability Block Map field. The Probability Block Map field may beprovided as one of the fields in the Band Info information element, asdiscussed above with reference to Table 9. The Probability Block Mapfield indicates the most likely probability blocks in which a controlchannel may be found by the mobile station. The probability blockmembers may be defined in accordance with Interim Standard 136.1(IS-136.1), Revision A, Section 6.3.1.1.1 for each frequency band. Formore information on IS-136.1, see for example TIA/EIA-IS-136.1-A, TDMACellular/PCS-Radio Interface-Mobile Station-Base StationCompatibility-Digital Control Channel, Telecommunications IndustryAssociation, October 1996, the disclosure of which is expresslyincorporated herein by reference in its entirety. TABLE 13 ProbabilityBlock Map Value Function 1XXX XXXX 1st probability block likely tocontain control XXXX XXXX channels 0XXX XXXX 1st probability blockunlikely to contain control XXXX XXXX channels . . . . . . XXXX XXXX16th probability block likely to contain control XXXX XXX1 channels XXXXXXXX 16th probability block unlikely to contain control XXXX XXX0channels

[0106] Table 14 illustrates the various fields that may be provided forthe System Access List information element. As discussed above, theSystem Access List information element may be included in theConfiguration Data Response message (see step S.212) and the DownloadRequest message (see step S.216). The System Access List informationelement may contain PSL/IRDB entries for the mobile station to use inidentifying the preferred system to access when in an intelligentroaming mode. As shown in Table 14, the System Access List informationelement may include a field to indicate the number of PSL/IRDB entriesthat are present (e.g., a Number of Target Systems field), and mayinclude one or more PSL/IRDB entries that are provided for each SIDincluded in the System Access List information element. The SystemAccess List information element may also include a coded Parameter Typefield (e.g., 0100) to indicate the parameter type. Table 15 illustratesan example of the fields for an PSL/IRDB entry, which is used toindicate the target or preferred systems for the mobile station whenroaming. TABLE 14 System Access List Field Length Parameter Type 4Number of PSL/IRDB Entries (S) 7 PSL/IRDB Entry (S + 1 instances of(S + 1) × (24 + 40 × T) this field are present)

[0107] TABLE 15 PSL/IRDB Entry Field Length Current SID 15  RoamIndicator 1 Scan Method 2 Scan Time 2 Number of Target Systems (T) 4Target System Info (T instances of this field are present) (40 × T)

[0108] As shown in Table 15, each PSL/IRDB entry may include a CurrentSID field to indicate the current SID that the entry is associated with,a Roam Indicator field to indicate the status of the roam indicator, aScan Method field to indicate the scan method to be utilized by themobile station, a Scan Time field to indicate the scan time, a Number ofTarget Systems field to indicate the number of preferred or targetsystems, and a Target System Info field for each target system. EachPSL/IRDB entry may be accessed by the mobile station by looking up theSID of the current system and comparing it with the Current SID field ofeach entry in the System Access List until a match is found. The RoamIndicator field may be used in each PSL/IRDB entry to indicate whetherthe roam indicator should be displayed by the mobile station for thecurrent system. For example, when the Roam Indicator field is set toone, this field will indicate that the mobile station should display theroam indicator. If, however, the Roam Indicator field is set to zero,the roam indicator should not be displayed by the mobile station.

[0109] The Scan Method field of each PSL/IRDB entry may indicate how themobile station should scan for a target system. Table 16 illustrates anexample of the coded values that may be assigned to the Scan Method bitfield, as well as the related function for each coded value. If, forexample, the Scan Method field has a value of zero, then the mobilestation should perform a continuous scan until it finds a target system.If, on the other hand, the Scan Method field is equal to one, then themobile station should obtain service on the current SID and scan fortarget or preferred systems periodically. TABLE 16 Scan Method ValueFunction 00 Continuous scan until find a target system 01 Obtain serviceon current SID and scan for target systems periodically

[0110] The Scan Time field of each PSL/IRDB entry indicates theapproximate interval between scans for a target system. Table 17illustrates various coded values that may be assigned to the Scan Timefield. The scan time interval may be set based upon various factors,including the operating conditions of the mobile station. For example,the battery power of the mobile station may effect the scan timeinterval, such that a longer scan time interval may be desirable toreduce the number of required scans and consumption of the battery. Byway of a non-limiting example, a scan time interval of two and one-halfor five minutes may be utilized. As shown in the embodiment of Table 17,if the Scan Time field is set to zero, then the scan time will be setsuch that the mobile station will perform a scan every two and one-halfminutes. If the scan time is set to one, then a longer scan time may beused by the mobile station. For example, in Table 17, a scan time fieldvalue of one would cause the mobile station to perform a periodical scanevery five minutes. TABLE 17 Scan Time Value Function 00 Periodicallyscan every 2½ minutes 01 Periodically scan every 5 minutes

[0111] As noted above, each PSL/IRDB entry may include a field toindicate the number of target systems (i.e., a Number of Target Systemsfield), and a field to indicate the target system information for eachtarget system (i.e., a Target System Info field). Target systeminformation may be provided for each target or preferred system thatexists for the current SID. The number of target systems for a currentSID will vary depending upon, for example, the reciprocal agreements orbilling arrangements that the home network provider has with providersfor the current SID. Table 18 illustrates an exemplary Target SystemInfo field and the information that may be included in the Target SystemInfo field. TABLE 18 Target System Info Field Length Target Band 3Technology Map 5 Target SID 15 Roam Indicator 1 Probability Block Map 16

[0112] As shown in Table 18, the Target System Info may include a TargetBand field which identifies the frequency band for a target or preferredsystem. The Target Band field may be coded in a similar manner to theHome Band field (see, for example, Table 12). A field to indicate theSID of the target system (i.e., a Target SID field), as well as a fieldto indicate the roam indicator display status for the target system(i.e., a Roam Indicator field) may also be provided. The Roam Indicatorfield of the Target System Info may indicate to the mobile station whena roaming status indication should be displayed when service is obtainedon a particular target system. When the Roam Indicator field is set toone, for example, this field may indicate that the mobile station shoulddisplay the roaming status indication. Otherwise, if the value of theRoam Indicator field is set to zero, the roaming status indicationshould not be displayed by the mobile station.

[0113] As part of the target system information in the Target SystemInfo data block, a Technology Map field may also be provided. TheTechnology Map field may identify the air-interface technologies (e.g.,EIA/TIA-553 (AMPS), IS-136, PCS-1900, etc.) and/or other technologiesassociated with a particular frequency band of a given target system.Table 19 illustrates examples of the various coded values that theTechnology Map field may be assigned to indicate a particularair-interface technology. In the embodiment of Table 19, the unassignedbit values may be held in reserve for future systems or applications(e.g., they could be assigned to PACS, CDMA, or other technologies).TABLE 19 Technology Map Value Function X XXX1 EIA/TIA-553 (AMPS) X XX1XIS-136 X X1XX PCS-1900

[0114] Other information relating to each target or preferred system mayalso be provided as part of the information fields for the Target SystemInfo. For example, a Probability Block Map field may be provided toindicate the most likely probability blocks in which a control channelmay be found. An example of the manner in which a Probability Block Mapfield may be coded is provided above with reference to Table 13.

[0115] In accordance with another embodiment of the present invention,the PSL/IRDB and intelligent roaming information may be downloaded andprogrammed into the mobile station by embedding the over-the-airprogramming messages within the SOC Specific Request message defined forOATS. According to this embodiment, the BMI will send the SOC SpecificRequest message to the mobile station (MS), and the MS will respond withthe R-DATA ACCEPT message. FIG. 6 illustrates an example of the messageflow between the MS and the BMI for over-the-air programming of themobile station in accordance with this embodiment of the presentinvention.

[0116] In the embodiment of FIG. 6, the intelligent roaming data willonly be committed to memory in the mobile station following a NAM CommitRequest message from the BMI, and a successful CSC Challenge. If needed,multiple SOC Specific Request messages may be sent to the MS prior to aNAM Commit Request in order to program all of the intelligent roamingdata.

[0117] At step S.300 in FIG. 6, an SOC Specific Request message is sentfrom the BMI to the MS. The SOC Specific Request message may be used forSOC Specific Data. Table 16 illustrates an example of the informationelements that may be included in each SOC Specific Request message. Asshown in Table 20, the SOC Specific Request message may be configuredaccording to the existing message defined for OATS. TABLE 20 SOCSpecific Request Information Element Type Length Message Type M  6Remaining Length (in Octets) M  8 System Operator Code (SOC) M 12 SOCSpecific Data M 0 −*

[0118] As shown in step S.304 of FIG. 6, multiple SOC Specific Requestmessages may be sent to the mobile station prior to the NAM CommitRequest, in order to program all of the necessary intelligent roamingdata. Each SOC Specific Request message may be used for SOC SpecificData. The SOC Specific Data may be provided as an information element ineach of the SOC Specific Request messages. Table 21A illustrates thevarious information elements and coded contents that may be provided asthe SOC Specific Data. When messages are sent, the SOC may be set to aparticular code corresponding to the service provider (e.g., 004 hex).The SOC Specific Data may include the Band Info and the System AccessList information elements, similar to that described above (see, forexample, Tables 9, 14 and 15). Table 21B illustrates an example of theparameter type codes for the optional information elements in the SOCSpecific Data information element of Table 21 A. TABLE 21A SOC SpeciticData Information Element Type Length Band Info 0 26 System Access List 035 −*

[0119] TABLE 21B Parameter Codes for Optional Information ElementsParameter Type Code Band Info 0001 System Access List 0010

[0120] After all of the SOC Specific Request messages have been sent, aNAM Commit Request message may be sent from the BMI to the MS at stepS.308. In response, a SOC Challenge Request message will be sent fromthe MS to the BMI at step S.312, and a CSC Challenge Response will bereturned by the BMI to the MS at step S.316. Thereafter, as shown inFIG. 6, a NAM Commit Result message will be sent at step S.320 from theMS to the BMI to confirm the programming of the intelligent roaming datato the mobile station.

[0121] Various techniques and network architectures may be utilized foradministering, programming and updating each mobile station with thePSL/IRDB and other intelligent roaming information. For example, asdiscussed above, a main or centralized database could be established toimplement the various aspects of the present invention. Such acentralized database could include information on all of the networksystems that the home service provider owns, as well as information onall the systems with which the service provider has preferred roamingagreements or billing arrangements. Entries in the database couldencompass, for example, all of the information that is provided to themobile station as part of the over-the-air programming of the mobilestation. Other information could also be included in such a centralizeddatabase. For example, the centralized database could contain for eachentry in the PSL/IRDB, the name of the cellular service provider foreach target or preferred system, a contact, and roaming agreementinformation.

[0122] In accordance with another aspect of the present invention, FIG.7 illustrates an exemplary network architecture for implementing andadministering the intelligent roaming capabilities and features of thepresent invention. In the embodiment of FIG. 7, a mobile station 168receives PSL/IRDB information via a centralized or master PSL/IRDBdatabase 192 that has one or more slave PSL/IRDB database arrangements186. The master PSL/IRDB 192 may be administered centrally by anoperator and may contain PSL/IRDB information and other intelligentroaming information for all of the systems that the service providerowns, and all of the systems with which the service provider haspreferred roaming agreements. The master PSL/IRDB 192 may comprise acomputer or workstation with memory, and a database application forstoring all of the PSL/IRDB information and other intelligent roaminginformation. The master PSL/IRDB 192 may also include a database thatindicates all of the mobile stations supporting the intelligent roamingcapabilities of the present invention.

[0123] Each of the slave PSL/IRDBs 186 may comprise logical entitieswithin, for example, an Over-The-Air Activation Function (OTAF). TheOTAF may comprise a software application residing on a computer orworkstation, and be adapted to store and forward information to beprogrammed into the mobile stations. The master PSL/IRDB 192 may updateall OTAF/slave PSL/IRDBs 186 with new information concerning target orpreferred systems as required or as information becomes available. Whenthe master PSL/IRDB 192 is updated with new PSL/IRDB information, eachof the OTAF/slave PSL/IRDBs 186 may receive the information from themaster PSL/IRDB 192 through, for example, a Transmission ControlProtocol/Internet Protocol (TCP/IP) connection, format the informationfor the mobile stations, and send the formatted information to themobile stations through the cellular or PCS network. Along with the newPSL/IRDB information sent from the master PSL/IRDB 192, a list of themobile stations requiring updating may be sent to all OTAF/slavePSL/IRDBs 186. Each of the OTAF/slave PSL/IRDBs 186 would then beresponsible for updating the mobile stations, and may keep track of themobile stations that have been updated with new intelligent roaminginformation and those that still require updating. Each of the mobilestations may be identified by its Mobile Identification Number (MIN) orInternational Mobile Station Identity (IMSI). The mobile stationidentity may also identify the mobile station's Home Location Register(HLR).

[0124] As noted above, each of the OTAF/slave PSL/IRDBs 186 may send theformatted information to the mobile stations through the cellular or PCSnetwork. The Base Station/Mobile Switching Center/Inter-Working Function(BMI) may be used to transfer the information to the mobile stations.When information is received from the master PSL/IRDB 192, theOTAF/slave PSL/IRDB 186 may send, for example, an Interim Standard 41C(IS-41C) message to the mobile station's HLR to determine the locationof the mobile station. The HLR may then respond with an address for theserving systems's MSC or MTSO (such as MTSO 154). As illustrated in FIG.7, the OTAF/slave PSL/IRDB 186 may then communicate over-the-airprogramming messages for the mobile station, such as mobile station 168,via MTSO 154 using the IS-41C SMS Delivery Point-to-Point (SMDPP)message. The MTSO 154 may then repackage the over-the-air message into,for example, an Interim Standard 136 (IS-136) R-DATA message fordelivery to the mobile station 168 through an appropriate base stationor cell site 175. Feedback may be provided by the serving MTSO 154 tothe OTAF/slave PSL/IRDB 186 (e.g., in the form of another IS-41Cmessage) to indicate whether the information successfully reached themobile station. If the information was not successfully delivered to themobile station, the OTAF/slave PSL/IRDB 186 could trigger a retrymechanism to resend the information.

[0125] Other features may be provided for administering and implementingthe intelligent roaming capabilities of the present invention. Forexample, as an alternative to the embodiment of FIG. 7, the home networksystem could broadcast a code indicating when the central PSL/IRDBdatabase was last updated. Based on this code, mobile stations couldthen determine periodically if they have the most current PSL/IRDBinformation. When it is determined that the PSL/IRDB informationcontained in the mobile station is not current, the mobile station couldrequest reprogramming by sending a request message using, for example,OATS message protocols.

[0126] While the invention has been described with reference to severalexemplary embodiments, it is understood that the words which have beenused herein are words of description and illustration, rather than wordsof limitations. Changes may be made, within the purview of the appendedclaims, as presently stated and as amended, without departing from thescope and spirit of the invention in its aspects.

[0127] For example, although a mobile station-based approach has beendisclosed for implementing the intelligent roaming features andcapabilities of the present invention, other approaches and methods maybe utilized to achieve and implement the various aspects of the presentinvention. For example, the present invention may be implemented througha network-based approach, whereby PSL/IRDB and preferred systeminformation is directed from a serving network to the mobile station inorder to obtain service on the preferred system. In such a case, some ormost of the “intelligence” may be provided in the network to facilitateroaming by the mobile station.

[0128] Further, although embodiments for over-the-air programming of thePSL/IRDB have been discussed with reference to OATS, over-the-airprogramming may be implemented as a different or separate teleservice.For example, over-the-air programming may be developed and standardizedas a completely new teleservice, or it may be developed as acarrier-specific teleservice. In addition, various over-the-airactivation methods or teleservices, including OATS, may be utilized inorder to activate new mobile station users. For example, activationinformation may be programmed in the mobile station using the DigitalControl Channel (DCCH) that is associated with IS-136, or an appropriatesignaling channel to communicate with a cellular network when not on avoice or data call. Alternatively, the activation information may beprogrammed in the mobile station using a Digital Traffic Channel (DTC),or an appropriate digital voice or data channel to communicate with acellular network. If over-the-air activation is performed on the DCCH orthe DTC, the new mobile station user may be required to initiate a callto a Customer Service Center (CSC), and to follow a predetermined set ofprocedures to perform over-the-air activation of the mobile station.

[0129] Although the invention has been described herein with referenceto particular means, materials and embodiments, the invention is notintended to be limited to the particulars disclosed herein; rather, theinvention extends to all functionally equivalent structures, methods anduses, such as are within the scope of the appended claims.

1. A mobile station for use in wireless communication comprising: amemory for storing a home area wireless network identity and a list of aplurality of preferred wireless network identities; and a controllercontrolling said mobile station to connect to the home area wirelessnetwork when in a home area and controlling said mobile station toconnect to one of the preferred wireless networks when outside the homearea.
 2. The mobile station for use in wireless communication of claim1, in which the memory further comprises the list of preferred wirelessnetwork identities that substantially optimizes use of a class ofservice.
 3. The mobile station for use in wireless communication ofclaim 1, in which the memory further comprises the list of preferredwireless network identities that substantially minimizes air-timeroaming rates.
 4. The mobile station for use in wireless communicationof claim 1, in which the memory further comprises the list of preferredwireless network identities that substantially optimizes use forspecific market areas.
 5. The mobile station for use in wirelesscommunication of claim 1, in which the memory further comprises the listof preferred wireless network identities that substantially optimizesuse for a predetermined national account.
 6. The mobile station for usein wireless communication of claim 1, in which the memory furthercomprises the list of preferred wireless network identities thatsubstantially optimizes use for an air-interface technology.
 7. Themobile station for use in wireless communication of claim 1, wherein thecontroller connects to the preferred wireless network identities in anorder of preference of the preferred wireless networks.
 8. A method ofusing a mobile station for wireless communication comprising: storing ahome area wireless network identification and a list of preferredwireless network identifications; and connecting a mobile station to thehome area network when in a home area and connecting to one of thepreferred wireless networks when outside the home area.
 9. The method ofusing a mobile station for wireless communication of claim 8 in whichthe list of preferred wireless networks comprises a list of preferredwireless networks that substantially optimizes use of a predeterminedclass of service.
 10. The method of using a mobile station for wirelesscommunication of claim 8 in which the list of preferred wirelessnetworks comprises a list of preferred wireless networks thatsubstantially minimizes air-time roaming rates.
 11. The method of usinga mobile station for wireless communication of claim 8 in which the listof preferred wireless networks comprises a list of preferred wirelessnetworks that substantially optimizes use of a predetermined nationalaccount.
 12. The method of using a mobile station for wirelesscommunication of claim 8 in which the list of preferred wirelessnetworks comprises a list of preferred wireless networks thatsubstantially optimizes use of specific market areas.
 13. The method ofusing a mobile station for wireless communication of claim 8 in whichthe list of preferred wireless networks comprises a list of preferredwireless networks that substantially optimizes use of an air-interfacetechnology.
 14. The method of using a mobile station for wirelesscommunication of claim 8 in which the list of preferred wireless networkidentifications is in an order of preference of the preferred wirelessnetworks.
 15. A method of using a mobile station for wirelesscommunication comprising: storing a home area network identification anda list of preferred network identifications; connecting a mobile stationto the home area network when in a home area and connecting to one ofthe preferred networks when outside the home area; and updating the homemarket network and the list of the preferred networks identifications.16. A method of using a mobile station for wireless communication ofclaim 15 wherein updating the list is initiated by a customer servicecenter.
 17. A method of using a mobile station for wirelesscommunication of claim 15 wherein updating the list is initiated by acustomer service center through at least one of over the air programingand over the air activation.
 18. A method of using a mobile station forwireless communication of claim 15 wherein updating the list isinitiated by a customer service center, delivered by a short messagingsystem (SMS), and completed through at least one of over the airactivation and over the air programing.
 19. A method of using a mobilestation for wireless communication of claim 15 wherein the list furthercomprises information on system identification of the preferrednetworks.
 20. A method of using a mobile station for wirelesscommunication of claim 19 wherein the system identification comprises atleast one of a scan method of the networks, scan time of the networks,number of targets of the networks, and target information of thenetworks.
 21. A method of using a mobile station for wirelesscommunication of claim 20 wherein the target information comprises atleast one of a target band, technology map, roam indicator, andprobability map.
 22. A method of providing wireless customer servicecomprising: generating a home area network and a list of preferredwireless network identities; downloading said list of preferred wirelessnetwork identities to at least one mobile station; and updating the listof preferred wireless network identities of at least one mobile stationas needed.
 23. The method of claim 22 in which the generating identitiesfurther comprises generating the list of preferred wireless networks tosubstantially minimize air-time roaming rates.
 24. The method of claim22 in which the generating identities further comprises generating thelist of preferred wireless networks to substantially optimizepredetermined use of a national account.
 25. The method of claim 22 inwhich the generating identities further comprises generating the list ofpreferred wireless networks to substantially optimize use of specificmarket areas.
 26. The method of claim 22 in which the generatingidentities further comprises generating the list of preferred wirelessnetworks to substantially optimize use of an air-interface technology.27. The method of claim 22 in which the generating identities furthercomprises generating the list of preferred wireless networks tosubstantially optimize a predetermined use of a class of service. 28.The method claim 22 in which the generating identities further comprisesgenerating the list of preferred wireless networks to include an orderof preference of the preferred wireless networks.
 29. The method ofclaim 22 wherein the downloading of the list is initiated by a customerservice center, delivered by a short messaging system (SMS), andcompleted through at least one of over the air activation and over theair programing.